Evidence that an ancient Pueblo site was built out of “golden rectangles”

This is a satellite photo of the Sun Temple
archaeological site in Colorado with illustrations demonstrating its
geometrical properties.

Sherry Towers

At Pueblo Bonito, in New Mexico's Chaco Canyon, we
can see a golden rectangle emerging out of the layout pattern just like
at the Sun Temple.

Sherry Towers

A millennium ago, the Pueblo peoples were
constructing incredible monuments and cities throughout the US
Southwest. Among the most impressive structures they left behind is
called the Sun Temple, in what is now Colorado's Mesa Verde National Park.
Probably the location for meetings and ceremonies, the Sun Temple is an
enormous D-shaped building with walls that were once 11-15 feet high.
Now, an applied mathematician has discovered something intriguing about
the proportions used to lay out the temple and its internal structures.

Physicist Sherry Towers is part of the
Mathematical, Computational, and Modeling Sciences Group at Arizona
State University, and she occasionally takes time away from physics to
focus on the way mathematical patterns shape the social world. She got
interested in the Sun Temple site because many archaeologists believe
its structure might reveal whether the Pueblo peoples were using it for
astronomy. But as Towers pored over satellite images of the area from
Google Maps, the Sun Temple's general shape kept drawing her attention.
"I noticed in my site survey that the same measurements kept popping up
over and over again," she said in a release.
"When I saw that the layout of the site's key features also involved
many geometrical shapes, I decided to take a closer look."

What she found was twofold. First, it appears
the Sun Temple was built using a common unit of measurement, which is
roughly 30 cm. This in itself is a fascinating discovery, because we
have no evidence that the Pueblo peoples had a written language or
number system. In a recent paper for Journal of Archaeological Science Reports,
Towers wrote that major structures at the site—namely, the retaining
wall and four round, tower-like "Kivas"—were "laid out with remarkable
precision, with the relative uncertainty on measurements estimated to be
approximately one percent."

More incredibly, she also found that "key
features of the site were apparently laid out using the Golden
rectangle, squares, 45◦ triangles, Pythagorean 3:4:5 triangles, and
equilateral triangles." She added that the "Sun Temple site thus likely
represents the first evidence of advanced knowledge of several
geometrical constructs in prehistoric America." Though ancient peoples
in Greece also used the golden rectangle in their constructions, this
would be the first evidence for a similar geometric structure in the
pre-contact Americas. It means that the Pueblo peoples' urban layouts,
which included cities carved into rockfaces and a sizable reservoir
system, were aided by a sophisticated understanding of geometry.

Many archaeologists are leery of making such
claims, because it's hard to know whether these shapes were intentional
or not. Towers explained that she's leery of this, too, but she
remains confident in her discovery:

Some individuals have pursued
pseudo-scientific studies of geometric layouts of archaeological sites,
and this unfortunately has led to a cachet of “woo science” associated
with any study in this area... for instance, in various studies
purporting evidence of geometric layouts associated with Southwest
prehistoric sites (often associated with New Age theories), the author
has noted that geometric shapes of arbitrary size are simply overlaid on
a map of a site, without regard to whether or not the vertexes, sides,
or size of the shape are meaningfully associated with any of the key
features of the site... To ensure rigor in our analysis, we thus only
examined potential geometries associated with either the size of key
features like the four Kivas and the outer D, or geometries associated
with measures between at least two of the key features. We also only
presented results that can be independently verified by interested
readers using aerial imagery available with software programs such as
Google Earth, and we assessed the statistical significance of the
apparent geometries we examined.

More study is needed to substantiate Towers'
claim, but she's taken the first important step. She hopes that
scientists can move on to study other ceremonial structures built by the
Pueblo peoples, such as Chaco Canyon in New Mexico, which may have been built using the same standard unit of measure she discovered at the Sun Temple.